Question

What is the perimeter, in cm, of quadrilateral ABCD if Line AB is perpendicular to Line BC, Line DC is perpendicular to Line BC, AB=9 cm, DC=4 cm, and BC=12 cm?
Please help, I don't know how to solve this, an explanation would be helpful too, Thank you.

Answer 1

Answer:

38cm

Step-by-step explanation:

The perimeter of the quadrilateral

ABCD=AB+BC+DC+AD.

From the question,

AB =9cm, BC=12cm and DC=4cm.

This implies that we need to find the length AD before we can proceed to find the perimeter.

From the diagram, we can find |AD| using Pythagorean Theorem.

${|AD|}^{2} = {12}^{2} +{5}^{2}$

${|AD|}^{2} =144+ 25$

${|AD|}^{2} =169$

Taking positive square root of both sides

$|AD|= \sqrt{169}$

$|AD|=13 \: cm$

Hence the perimeter

=9+12+4+13

=38cm